Method of producing cellulose threads.



EDMUND THIELE, OF BRUSSELS, BELGIUM.

METHOD OF PRODUCING CELLULOSE THREADS.

Specification of Letters Patent.

Patented Jan. 12, 1909.

Application filed. June 23, 1906. Serial No. 323,071.

To all whom it may concern:

Be it known that I, EDMUND TIIIELE, a citizen of the Empire of Germany, residing at Brussels, in the Kingdom of Belgium, have invented a new and useful Method of Producing Cellulose Threads, of which the following is a specification.

The known method of producin -threads from concentrated solutions of ce lulose in ammoniacal solution of cupric oXid with the aid of slowly acting precipitants and of subsequent] y stretching the threads presents the defect, that the threads frequently stick together and therefore furnish a hard, strawy, little bright product. This defect may be obviated by the employment of an alkaline precipitation-liquid, in which the precipitation and the stretching of the threads are effected, so that soft and bright threads are obtained.

My invention relates to a more advantageous method, in which the threads are first precipitated and stretched in a sour or neutral or little alkaline slowly acting p1'e-.

cipitation-liquid and are afterwards treated with. alkaline baths, more particularly with a caustic lye.

The new method is as follows: A concentrated solution of cellulose in ammoniacal solution of cupric oxid is in a known manner permitted to issue from comparatively wide apertures (of about half a millimeter diam eter) into pure water or water with a little acid or alkali. The threads so formed are stretched or'drawn out either by rapidly winding them on a roll or by dropping them i through a high head of the precipitationliquid. Afterwards the threads .are drawn through a cold caustic soda of 39 Baum or through a hot (boiling) lye which is a little less concentrated (but which has a more powerful action than the cold lye) and at last they are treated with acid either at once or during their winding on a drum or after a little time. When hot (boiling) lye is used the resulting threads or "fibers show a luster and brilliancy much greater than when cold lye is used.

The-method may be varied without departing from the spirit of my invention.

I claim:

1. The method of producing cellulose threads, which consists in )ermitting a concentrated solution of cellulose in ammoniac copper to issue from comparatively wide apertures into a slowly acting precipitation bath, drawing out the threads so formed in this bath, and subse uently treating them with a boiling caustic ye.

2. The method of roducing cellulose threads, which consists in permitting concentrated solution of cellulose in ammoniac copper .to issue from comparatively wide apertures into a diluted caustic lye, drawing out the threads so formed in this bath, and

subsequently treating them with a boiling caustic lye.

EDMUND THIELE.

Witnesses:

v OTTO Konre,

ADoLr SCHUBERT. 

